Mixed-valence complex electrodes for a rechargeable electrical energy storage device

Abstract

An electrode for a rechargeable electrical energy storage device has a substrate and an electrochemically active material deposited on the substrate. The electrochemically active material provides electron transfer between itself and an electrolyte. The electrochemically active material is a mixed-valence complex containing at least two metal atoms and at least one ligand attached to the metal atoms, and has metal-to-metal bonds where the metals exist in multiple oxidation states such that electron transfer between the metal atoms in the complex or between discrete complexes occurs. A rechargeable electrical energy storage device (20) has two electrodes (28, 36) constructed from a mixed-valence complex (30), and the electrodes are electrically connected by an ion carrying electrolyte (32). The electrodes are also physically separated from each other by a barrier (34) that will pass ions but not electrons.

What is claimed is: 
     
       1. An electrode for a rechargeable electrical energy storage device, comprising: a substrate;   an electrochemically active material deposited on the substrate, the electrochemically active material providing electron transfer between itself and an electrolyte; and   the electrochemically active material comprising a mixed-valence complex containing at least two metal atoms and at least one ligand attached to the metal atoms, and having metal-to-metal bonds where the metal atoms exist in multiple oxidation states such that electron delocalization or transfer between atoms in the complex or between discrete complexes can occur.   
     
     
       2. The electrode for a rechargeable electrical energy storage device as described in claim 1, wherein the at least two metal atoms comprise different metals. 
     
     
       3. The electrode for a rechargeable electrical energy storage device as described in claim 1, wherein the formal oxidation state of the metal in the complex is non-integral. 
     
     
       4. The electrode for a rechargeable electrical energy storage device as described in claim 1, wherein the mixed-valence complex is a salt. 
     
     
       5. The electrode for a rechargeable electrical energy storage device as described in claim 1, further comprising more than one mixed valence complex per electrode. 
     
     
       6. The electrode for a rechargeable electrical energy storage device as described in claim 1, wherein the mixed-valence complex is selected from the group consisting of platinum blues, platinum reds, platinum greens, and platinum purples. 
     
     
       7. The electrode for a rechargeable electrical energy storage device as described in claim 6, wherein the mixed-valence complex is cis-diammineplatinum alpha pyridone blue. 
     
     
       8. The electrode for a rechargeable electrical energy storage device as described in claim 1, wherein the mixed-valence complex is tetracyanoplatinate complexes with stacked anions. 
     
     
       9. A rechargeable electrical energy storage device, comprising; an electrochemical cell having two electrodes, at least one electrode comprising a mixed-valence complex containing at least two metal atoms and at least one ligand attached to the metal atoms, and having metal-to-metal bonds where the metals exist in multiple oxidation states such that electron delocalization or transfer between the metal atoms in the complex or between discrete complexes occurs; and   an ion carrying medium electrically connecting and physically separating the electrodes.   
     
     
       10. The rechargeable electrical energy storage device as described in claim 9, wherein either of the two electrodes may be the anode or negative electrode. 
     
     
       11. The rechargeable electrical energy storage device as described in claim 9, wherein either of the electrodes may be the cathode or positive electrode. 
     
     
       12. The rechargeable electrical energy storage device as described in claim 9, wherein the mixed-valence complex is selected from the group consisting of platinum blues, platinum reds, platinum greens, and platinum purples. 
     
     
       13. The rechargeable electrical energy storage device as described in claim 12, wherein the mixed-valence complex is cis-diammineplatinum alpha pyridone blue. 
     
     
       14. The rechargeable electrical energy storage device as described in claim 9, wherein the mixed-valence complex is tetracyanoplatinate complexes with stacked anions. 
     
     
       15. The rechargeable electrical energy storage device as described in claim 9, further comprising a current collector, wherein the current collector is coated with the mixed-valence complex. 
     
     
       16. The rechargeable electrical energy storage device as described in claim 9, wherein the formal oxidation state of the metal in the complex is non-integral. 
     
     
       17. The rechargeable electrical energy storage device as described in claim 9, wherein each electrode comprises a different mixed-valence complex. 
     
     
       18. An electrical energy storage device comprising: a rechargeable electrochemical cell having two electrodes and an electrolyte, at least one of the electrodes having a surface comprising an electrochemically active material that provides electron delocalization or transfer between the electrolyte and the electrochemically active material;   the electrodes separated by a barrier that passes ions but not electrons; and   the electrochemically active material comprising one or more mixed-valence complexes containing at least two metal atoms and at least one ligand attached to the metal atoms, and having metal-to-metal bonds where the metals exist in multiple oxidation states such that electron transfer between atoms in the complex or between discrete complexes can occur.   
     
     
       19. The electrical energy storage device as described in claim 18, wherein the formal oxidation state of the metal in the complex is non-integral.